A föhn wind or foehn wind occurs when a deep layer of prevailing wind is forced over a mountain range. As the wind moves upslope, it expands and cools, causing water vapor to precipitate out. This dehydrated air then passes over the crest and begins to move downslope. As the wind descends to lower levels on the leeward side of the mountains, the air heats as it comes under greater atmospheric pressure creating strong, gusty, warm and dry winds. Föhn winds can raise temperatures as much as 30°C (50°F) in just a matter of hours. Winds of this type are called "snow-eaters" for their ability to make snow melt rapidly. This ability is based on not only the high temperature, but also the low relative humidity of the air mass. Wind is the quasi-horizontal movement of air (as opposed to an air current) caused by a horizontal pressure gradient force. ... Mount Cook, a mountain in New Zealand A mountain is a landform that extends above the surrounding terrain in a limited area. ... General properties of water vapor Evaporation/sublimation Whenever a water molecule leaves a surface, it is said to have evaporated. ... Leeward is the side of a boat away from the direction where the wind is coming (i. ... diurnal (daily) rhythm of air pressure in northern Germany (black curve is air pressure) Atmospheric pressure is the pressure above any area in the Earths atmosphere caused by the weight of air. ... Temperature is the physical property of a system which underlies the common notions of hot and cold; the material with the higher temperature is said to be hotter. ... The degree Celsius (°C) is a unit of temperature named after the Swedish astronomer Anders Celsius (1701–1744), who first proposed a similar system in 1742. ... Fahrenheit is a temperature scale named after the German physicist Gabriel Fahrenheit (1686–1736), who proposed it in 1724. ... This page is about the form of precipitation. ... Physics In physics, melting is the process of heating a solid substance to a point (called melting point) where it turns liquid. ... Humidity is the concentration of water vapor in the air. ...

The name "föhn" (from the German Föhn, roughly pronounced "fern") originated in the Alps, and central Europe enjoys a warmer climate due to them. AEG registered the trademark "Fön" in the 1920s for its hairdryer, which is widely used as a synonym in the German language. Regionally, these winds are known by many different names. These include: The Alps is the collective name for one of the great mountain range systems of Europe, stretching from Austria in the east, Slovenia, Italy, Switzerland, Liechtenstein and Germany, through to France in the west. ... World map showing location of Europe A satellite composite image of Europe Europe is geologically and geographically a peninsula, forming the westernmost part of Eurasia. ... This is about the electronics producer. ...

• "Zonda winds" in Argentina
• "Chinook winds" in the Rocky Mountains, United States/Canada and the Chugach Mountains of Alaska, United States
• "Diablo winds" in the San Francisco Bay Area, United States
• "Santa Ana winds" in Southern California, United States
• "The Nor'wester" in southern New Zealand
• "Halny" in the Carpathians
• "Fogony" in the Catalan Pyrenees

Zonda wind is a regional term for the foehn wind that often occurs in Andes of Argentina. ... Chinook has several meanings: The Chinookan nation of Native Americans of the Pacific Northwest, which inhabited the lower Columbia River valley in what is now Washington, Oregon, and British Columbia. ... Rocky Mountain National Park (photo courtesy of NPS) The Rocky Mountains, often called the Rockies, are a broad mountain range in western North America. ... The Chugach Mountains of southern Alaska are the northernmost of the several mountain ranges that make up the Coast Ranges of the western edge of North America. ... State nickname: The Last Frontier, The Land of the Midnight Sun Other U.S. States Capital Juneau Largest city Anchorage Governor Frank Murkowski Official languages English Area 1,717,854 km² (1st)  - Land 1,481,347 km²  - Water 236,507 km² (13. ... Diablo wind is a regional term for the foehn wind that often occurs in the San Francisco Bay Area. ... USGS Satellite photo of the San Francisco Bay Area. ... Santa Ana winds are warm, dry winds that characteristically appear in Southern California weather during autumn and early winter. ... Southern California Los Angeles, rush hour on the Harbor Freeway San Diego Southern California, sometimes abbreviated SoCal, is an informal name for the southern one-third of the state of California. ... The Norwest arch is a weather pattern peculiar to the east coast of New Zealands South Island. ... This is about the terrestrial mountain range. ... Capital Barcelona Official languages Spanish and Catalan In Val dAran, also Aranese. ... Central Pyrenees The Pyrenees (French: Pyrénées; Spanish: Pirineos; Occitan: Pirenèus or Pirenèas; Catalan Pirineus; Aragonese: Perinés; Basque: Pirinioak) are a range of mountains in southwest Europe that form a natural border between France and Spain. ...

See also

• Katabatic wind

A katabatic wind, from the Greek word katabatikos meaning going downhill, is a wind that blows down a topographic incline such as a hill, mountain, or glacier. ...

External links

• Illustration (http://www.bom.gov.au/lam/glossary/fpagegl.shtml#fo)